The 4 gadgets that defined the Las Vegas Consumer Electronics Show

LAS VEGAS--The world's largest gadget show wrapped up on Friday, and the organizers said it was the biggest ever, beating last year's record in terms of the floor space companies purchased to display their wares.

What was it that drew more than 3,500 companies and 150,000 people to Las Vegas for this mega-event? Here are four gadgets that exemplified the top trends at this year's International CES.

Sony's 55-inch (140-centimeter) Ultra-high-definition TV

The introduction of high-definition and flat-panel TVs sent U.S. shoppers on a half-decade buying spree as they tossed out old tube sets. Now that the old sets are mostly gone, sales of new TVs are falling. To lure buyers back, Asian TV makers are trying to pull the same trick again. They're making the sets sharper. This fall, Sony and LG introduced 84-inch (213-centimeter) sets with four times the resolution of regular high-definition sets. They provide stunning sharpness, but they're too big for most homes, and at more than US$20,000, too expensive. At the show, the companies unveiled smaller "ultra-high-definition" sets, measuring 55 inches (140 centimeters) and 65 inches (165 centimeters) on the diagonal. They will go on sale this spring. Prices were not announced, but will presumably be a lot lower than for the 84-inch (213-centimeter) sets, perhaps under US$10,000.

Both the size and price of these smaller ultra-HD TVs should make them easier buys, but the higher resolution will be a lot less noticeable on a smaller screen, unless viewers sit very close. Analysts expect ultra-HD to remain an exclusive niche product for some years. There's no easy way to get ultra-HD video content to the sets, so they will mostly be showing regular HD movies. However, the sets can "upscale" the video to make it look better than it does on a regular HD set.

LG's 55-inch (140-centimeter) OLED TV

Organic light-emitting diodes, or OLEDs, make for thin, extremely colorful screens. They're already established in smartphone screens, and they have a lot of promise for other applications as well. For years, a promise is all they've represented. OLED screens are very hard to make in larger sizes. Now, LG is shipping a 55-inch (140-centimeter) OLED TV set in Korea, and is expected to bring it to the U.S. this spring for about US$12,000.